Sound quality and transient analysis

The quality of the sound - the quality of the sound

The standard definition and understanding of the two words "sound quality" and "sound effect" are difficult to have a unified standard, mainly depending on everyone's own feelings. Therefore, it leads to endless debate. Based on the understanding of sound and player, combined with my own experience, the author puts forward the following viewpoints:

The quality of sound is the quality of sound and the quality of sound. The specific description of sound includes sound, tone, timbre and sound. If it is difficult to understand, it can be compared with digital photographs.

If the color of a photograph is very pure, the level of detail is very rich and the brightness is very accurate, we can say that the unit of this picture has good quality. We can deal with the photos by the picture processing software, which can deepen the color concentration, strengthen the contrast, sharpen it, or add some artistic effects. In this way, we seem to be more beautiful, but in fact, we have already destroyed the original image quality (note the clouds in the sky below).

Before treatment

After treatment

The second picture looks like spring after the decoration, but this is a photo taken in winter.

The same is true of the sound quality. We adjust the equalizer to strengthen the high and low tone, add the DFX plug-in and so on, which makes us sound more pleasing to the ears. In fact, the details of a lot of sounds have been lost.

Sometimes it is essential for us to process and modify sounds or images, which is more in line with personal appreciation needs. However, we should not enhance the quality of sound. In short, the more we deal with it, the more plug-ins will be, and the more we will destroy the sound quality. To put it another point, many people are now comparing what sound software is good. Comparison is not impossible, but we must know how to compare, otherwise we will only give people ignorance.

We usually listen to music more or less with plug-ins, but in fact, this time we compare only sound effects, not sound quality. If we remove the effect of the sound effect, we actually compare the decoder of the software, and it is almost impossible to travel on a business trip if the software is used by the same decoder. Even with different decoders, MP3 decoding is basically a mature technology. Although there is a difference, it is very small. For our general player, claiming to be able to distinguish is self deception. Or do not know that they compare only sound effects, not sound quality.

The main terms of the evaluation of sound quality are:

Voice break (splitting): serious harmonic and intermodulation distortion, with "puff", has been cut flat top, distortion greater than 10%.

Sound hard: harmonic and intermodulation distortion, the instrument is clearly detected, distortion 3% to 5%.

There are two kinds of aberrations in voice burst: high frequency or high frequency.

Sound sand: medium and high frequency distortion, transient intermodulation distortion.

Rough voice: there are distortions, a little more in middle and high frequency, and a transient intermodulation distortion.

Voice is muddy: transient is not good, earphone loudspeaker resonance peak is prominent, low frequency or medium low frequency is excessive.

Wide Voice: wide frequency band, medium low frequency, low frequency, moderate reverberation.

The voice is stuffy: high frequency or medium high frequency is too few, or directivity is too sharp and deviates from the axis.

The sound is slender: high frequency, medium and high frequency, moderate distortion, good transient and no transient intermodulation distortion.

There are layers of sound: good transient, flat frequency and moderate reverberation.

Sound solid: medium and low frequency, moderate reverberation and loudness.

Voice divergence: medium frequency is lacking, intermediate frequency is not good, and reverberation is excessive.

Narrow voice: frequency characteristics are narrow, for example, only 150Hz to 4000Hz.

Metallic sound (lead skin sound): high and medium frequency points are prominent, and distortion is serious.

The sound is round: the frequency characteristic and distortion index are all good, the reverberation is moderate, the transient is good.

Sound has moisture: medium high frequency and high frequency, good reverberation.

Sound is bright: medium high frequency and high frequency enough, relatively flat, reverberation moderate.

Sound spines: high frequency and high medium and high frequency.

High pitch (floating): lack of medium frequency, high frequency and high frequency pointing too sharp.

Dark voice: lack of high frequency and middle and high frequency.

Sound hair dry: lack of reverberation, lack of middle and high frequency.

The sound is straight (wood): there is distortion, there are prominent points in low and low frequency, less reverberation and transient difference.

Sound balance (concordance): good frequency characteristics and small distortion.

Roar: the resonant peak of earphone loudspeaker is serious, and distortion and transient are not good.

Clear voice: medium high frequency and high frequency, small distortion, good transient.

The sound is three-dimensional (mono mode): the frequency response is flat, the reverberation is moderate, the distortion is small, the transient is good.

Sound transparency: high frequency and moderate high frequency, small distortion and good transient.

The voice has the sense of scene (telepresence): the frequency response is good, especially the middle and high frequency is good, the distortion is small, the transient is good.

Sound fullness: wide frequency band, medium low frequency, moderate reverberation.

Soft voice (loose): low frequency and moderate low frequency, distortion is very small.

Sound is bold and powerful: loudness, good reverberation, low frequency and medium low frequency.